From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AB4ED13777E; Tue, 16 Jun 2026 18:42:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781635357; cv=none; b=ESlB3RP4mb0Mx217gvBEbp4j66YiOaj/RZz1ZkJ9wdUADwt2HvOpheoAH+m1sY2zbfJ5lwTotgt+9KekqUVdEOsQVBXILRfzT3BKymgXYbvnrckyGJxZD6ZRvIDGX56aI8eppp6i914yZjOJMiPU31qZnqkQNQosTPZYEi8+8vg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781635357; c=relaxed/simple; bh=jyCzQbCRrPfi9LTFtc7yCT2773H2bczZjN1EmwFH81A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=gQwABRrZKDpII2YMUc58tF9I3vMuMWUT111LzxTh3UCMKmxtvNbaumq7i9nOtECWZougjPMjX1gXlvIEm1VF4Q89G4qYP/T8kIohmCoyc1pXoqOQm8pLJWwR3nAkf00RwpeA/SD4VtA/vdN5xK8TcK3eTem8SHvl/ZJq75dIPw4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=yFtki9dz; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="yFtki9dz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 942141F000E9; Tue, 16 Jun 2026 18:42:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1781635356; bh=rdQUSzBIpN0pAJz/IaBW9JuIYROtMr6kRwvN6PVsIRY=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=yFtki9dzfnqrQVR20E7HJUcBwISmQQDxOa4FOESxfPTwlFER587ZMnLWcLAg71EjW l5lC1lGAiazEoNb68sFIbO34cK+bK2Mi0bcBSrWkK46R1mUgp4uko+8NJp3bJw3acd 0hBd1zoSc9+MdrcNI51EAKTD7U7U7t/ohDL5pYpg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, stable@kernel.org, Yuan Tan , Yifan Wu , Juefei Pu , Xin Liu , Sven Eckelmann , Sasha Levin Subject: [PATCH 5.10 033/342] batman-adv: tvlv: reject oversized TVLV packets Date: Tue, 16 Jun 2026 20:25:29 +0530 Message-ID: <20260616145049.795165575@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260616145048.348037099@linuxfoundation.org> References: <20260616145048.348037099@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sven Eckelmann commit f50487e3566358b2b982b7801945e858c78ad9ab upstream. batadv_tvlv_container_ogm_append() builds a TVLV packet section from the tvlv.container_list. The total size of this section is computed by batadv_tvlv_container_list_size(), which sums the sizes of all registered containers. The return type and accumulator in batadv_tvlv_container_list_size() were u16. If the accumulated size exceeds U16_MAX, the value wraps around, causing the subsequent allocation in batadv_tvlv_container_ogm_append() to be undersized. The memcpy-style copy that follows would then write beyond the end of the allocated buffer, corrupting kernel memory. Fix this by widening the return type of batadv_tvlv_container_list_size() to size_t. In batadv_tvlv_container_ogm_append(), check the computed length against U16_MAX before proceeding, and bail out as if the allocation had failed when the limit is exceeded. Cc: stable@kernel.org Fixes: ef26157747d4 ("batman-adv: tvlv - basic infrastructure") Reported-by: Yuan Tan Reported-by: Yifan Wu Reported-by: Juefei Pu Reported-by: Xin Liu Reviewed-by: Yuan Tan Signed-off-by: Sven Eckelmann Signed-off-by: Sasha Levin --- net/batman-adv/tvlv.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/net/batman-adv/tvlv.c b/net/batman-adv/tvlv.c index 75f7ea827ed9dd..8da8184a2ebdfc 100644 --- a/net/batman-adv/tvlv.c +++ b/net/batman-adv/tvlv.c @@ -13,6 +13,7 @@ #include #include #include +#include #include #include #include @@ -160,10 +161,10 @@ batadv_tvlv_container_get(struct batadv_priv *bat_priv, u8 type, u8 version) * * Return: size of all currently registered tvlv containers in bytes. */ -static u16 batadv_tvlv_container_list_size(struct batadv_priv *bat_priv) +static size_t batadv_tvlv_container_list_size(struct batadv_priv *bat_priv) { struct batadv_tvlv_container *tvlv; - u16 tvlv_len = 0; + size_t tvlv_len = 0; lockdep_assert_held(&bat_priv->tvlv.container_list_lock); @@ -316,13 +317,17 @@ int batadv_tvlv_container_ogm_append(struct batadv_priv *bat_priv, { struct batadv_tvlv_container *tvlv; struct batadv_tvlv_hdr *tvlv_hdr; - u16 tvlv_value_len; + size_t tvlv_value_len; void *tvlv_value; int tvlv_len_ret; bool ret; spin_lock_bh(&bat_priv->tvlv.container_list_lock); tvlv_value_len = batadv_tvlv_container_list_size(bat_priv); + if (tvlv_value_len > U16_MAX) { + tvlv_len_ret = -E2BIG; + goto end; + } ret = batadv_tvlv_realloc_packet_buff(packet_buff, packet_buff_len, packet_min_len, tvlv_value_len); -- 2.53.0